The designer must identify all possible interaction states, navigation paths, list requests, queries, backtracks etc. The user should always be informed about the current interaction state so as to minimize disorientation. The system should also allow the user to "peek" at a destination (before reaching it) by highlighting all the nodes and links connected to the specific node. The system can also inform the user about the node and link types in the user's language. For example, if a detail node has an elaboration link to a footnote (another detail node), then the user should be informed through a feedback mechanism - "See associated footnote for further explanation of this concept". All user interactions can be stored in a history file so that the user can revisit the previously visited nodes the next time he or she brings up the system. Guided tours can be considered as a set of pre-defined interaction states or trails. Restoring previous interaction states to the way they were originally seen is very important for backtracking mechanisms [16].